Semiconductor device, radiation detection device, and radiation detection system

ABSTRACT

By forming a redundant circuit of an extra wiring accompanied with no decrease in an aperture ratio for a photoelectric conversion element, the yield is prevented from being reduced due to wire breaking during a panel manufacturing process.  
     A gate line Vg 4  and a Vg redundant wiring are electrically insulated and are arranged so as to form a crossing G of the upper and lower lines. Since a Vg redundant wiring Y is formed concurrently with a Sig line, there is no need for additional manufacturing steps to form the Vg redundant wiring Y. If a breaking occurs in the gate line Vg 4,  the gate line Vg 4  and the Vg redundant wiring Y are electrically connected to each other by irradiating the crossing G with a laser. Therefore, a gate drive pulse is also applied to a thin film transistor on the broken line through the Vg redundant wiring Y. Thus, any lowering in yield due to a breaking of the gate line Vg 4  can be prevented without any decrease in the aperture ratio for the photoelectric conversion element.

BACKGROUND OF THE INVENTION Related Background Art

[0001] The present invention relates to a semiconductor device, andparticularly, to a photoelectric conversion device, an area sensor, anda radiation imaging (or image pickup) apparatus having photoelectricconversion elements arranged in a matrix.

[0002]FIG. 11 is an equivalent circuit diagram of a prior artphotoelectric conversion device.

[0003] In FIG. 11, reference numerals P11 to P44 denote semiconductorelements such as photoelectric conversion elements and referencenumerals T11 to T44 denote thin film transistors (TFT). As shown in thefigure, the gate electrode of each TFT is generally connected to commongate lines Vg1 to Vg4. Each of the gate lines controls the ON/OFFoperations of the TFTs.

[0004] The source or drain electrode of each TFT is connected to commonsignal lines Sig1 to Sig4, which are connected to a readout unit.Electric charge generated in the semiconductor elements such asphotoelectric conversion elements due to incident visible light orradiation is transferred to the signal lines with gate drive pulsesapplied by a gate drive unit and is then read out by the readout unit.

[0005]FIG. 12 is a plan view of the photoelectric conversion deviceshown in FIG. 11. As shown in the figure, an additional wiring isprovided above the Vg lines as a redundant wiring for Vg lines (Vgredundant wiring) and is joined to the Vg lines through contact holes.

[0006]FIG. 13 is a plan view and a sectional view for showing the layerconfiguration of one pixel in a semiconductor device. The semiconductordevice comprises, on an insulating substrate, a semiconductor elementsuch as a photoelectric conversion element, a radiation detectionelement, or the like which is comprised of a first electrode layer, aninsulating layer, a first semiconductor layer, an n⁺-type semiconductorlayer, and a second electrode layer, and a switching TFT which iscomprised of a gate electrode layer, a gate insulating layer, a secondsemiconductor layer, and an ohmic contact layer. Each Vg line isconnected to an electrode layer in which the TFT gate electrode isformed and each Sig line is connected to a layer which forms thesource/drain electrode.

[0007] However, evolution in manufacturing technology for liquid crystalpanels using TFTs and increased applicability of area sensors havingphotoelectric conversion elements to various fields (for example, anX-ray imaging apparatus) have accelerated the development of TFT panelswith a larger area. With the enlargement of the area, the pattern pitchbecomes finer and finer.

[0008] This trend results in lowering of the yield of the panelmanufacturing process. Possible causes would be as described below.

[0009] Firstly, panels with a larger area have an increased wiringlength per panel, which may increase the breaking probability.

[0010] Secondly, a finer pattern brings about enlargement of the TFTarea or wire crossing area per panel, which may cause a higherprobability of short-circuiting between upper and lower metal wiringsdue to foreign matters.

[0011] Thirdly, a larger panel size requires a larger area where a panelis in contact with apparatuses for transporting and handling the panel,and thus, may generate a larger amount of static electricity with ahigher probability of generation of defects due to electrostaticdestruction (ESD).

[0012] The yield may be improved by solving the abovementioned technicalproblems and in particular, the breaking problem may be solved with alarger wiring width.

[0013] However, a wider wiring may increase the capacitance of acapacitor formed between the upper and lower metal wirings such as acrossing of a Sig line and a Vg line to decrease the sensitivity of asignal to be transferred.

[0014] Additionally, if a redundant wiring is formed for each wiring asa remedy for possible breaking, the aperture ratio of a photoelectricconversion element section may decrease with a further decrease in thesensitivity.

[0015] As described above, it is very difficult to appropriately designthe wiring width, redundant circuit, and so on.

SUMMARY OF THE INVENTION

[0016] Therefore, it is an object of the present invention to form aredundant circuit accompanied with no decrease in aperture ratio toprevent the yield from being lowered due to wire breaking during thepanel manufacturing process.

[0017] In the light of the above mentioned problems, the presentinvention prevents lowering in a yield of a fabrication process withoutany decrease in aperture ratio for a photoelectric conversion device, aradiation detection device, or the like.

[0018] The above mentioned object is attained by a semiconductor deviceof the present invention, which comprises a plurality of semiconductorelements, a plurality of switching elements, a plurality of drive linesfor driving the switching elements, and a plurality of signal lines forreading out an electric charge detected by the semiconductor elementsprovided on an insulating substrate, the semiconductor device furthercomprising a redundant wiring which forms a plurality of crossings withat least one of the drive lines and the signal lines and is electricallyinsulated from the at least one of the drive lines and the signal linesat each crossing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019]FIG. 1 is an equivalent circuit diagram for showing a firstembodiment of the semiconductor device according to the presentinvention;

[0020]FIG. 2 is a plan view for showing the first embodiment of thesemiconductor device according to the present invention;

[0021]FIG. 3 is an enlarged plan view of a crossing G shown in FIGS. 1and 2 and a sectional view thereof;

[0022]FIG. 4 is an enlarged plan view of a crossing S shown in FIGS. 1and 2 and a sectional view thereof;

[0023]FIG. 5 is an equivalent circuit diagram for showing a secondembodiment of the semiconductor device according to the presentinvention;

[0024]FIG. 6 is an equivalent circuit diagram for showing a thirdembodiment of the semiconductor device according to the presentinvention;

[0025]FIG. 7 is an equivalent circuit diagram for showing a fourthembodiment of the semiconductor device according to the presentinvention;

[0026] FI G. 8 is an equivalent circuit diagram for showing a fifthembodiment of the semiconductor device according to the presentinvention;

[0027]FIG. 9 is a schematic sectional view for showing an embodiment ofthe radiation detection device according to the present invention;

[0028]FIG. 10 is a schematic plan view for showing the embodiment of theradiation detection device according to the present invention;

[0029]FIG. 11 is an equivalent circuit diagram of a prior artphotoelectric conversion device;

[0030]FIG. 12 is a plan view of the photoelectric conversion deviceshown in FIG. 11;

[0031]FIG. 13 is a plan view and a sectional view for showing the layerconfiguration of one pixel of a semiconductor device;

[0032]FIGS. 14A and 14B are a schematic block diagram and a schematicsectional view for showing an example of the radiation detection deviceto which the present invention is applied, respectively; and

[0033]FIG. 15 is a system block diagram for showing an example of theradiation detection system according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] Now, embodiments of the present invention will be described indetail with reference to the attached drawings.

[0035] [Embodiment 1]

[0036]FIG. 1 is an equivalent circuit diagram for showing asemiconductor device according to a first embodiment of the presentinvention.

[0037] In FIG. 1, reference numerals P11 to P44 denote semiconductorelements such as photoelectric conversion elements, radiation detectionelements or the like and reference numerals T11 to T44 denote switchingelements such as TFTs or the like. The gate electrode of each TFT isconnected to gate lines Vg1 to Vg4 which are common drive wirings. Thegate lines Vg1 to Vg4 are connected to a gate drive unit which controlsthe ON/OFF operations of the TFTs. The source or drain electrode of eachTFT is connected to common signal lines Sig1 to Sig4, which areconnected to a readout unit.

[0038] In addition, an extra wiring (Vg redundant wiring) connected tothe gate drive unit acts as a redundant wiring for the Vg lines andforms a crossing with each Vg line outside a pixel area. Another extrawiring (Sig redundant wiring) connected to the readout unit acts as aredundant wiring for the Sig lines and forms a crossing with each Sigline outside the pixel area.

[0039] Here, the Vg redundant wiring consists of a Vg redundant wiring Xand a Vg redundant wiring Y and they are joined to each other through acontact hole at a point C in the figure. Also, the Sig redundant wiringconsists of a Sig redundant wiring X and a Sig redundant wiring Y andthey are joined to each other through a contact hole at the point C inthe figure. The above described Vg redundant wiring and Sig redundantwiring are formed outside the pixel area.

[0040] A electric charge generated in the semiconductor elements such asphotoelectric conversion elements due to incidence of visible light orradiation is transferred to the signal lines with gate drive pulsesapplied by the gate drive unit and is then read out by the readout unit.

[0041]FIG. 2 is a plan view of the photoelectric conversion device shownin FIG. 1.

[0042]FIG. 3 is an enlarged plan view showing an example of the layerconfiguration of a crossing G shown in FIGS. 1 and 2 and a sectionalview thereof. In FIG. 3, the Vg line and the Vg redundant wiring areelectrically insulated from each other and are arranged so as to form acrossing of the upper and lower lines. In the configuration as shown inthe figure, if the semiconductor layer has a considerably smallerelectric conductivity than the wirings (lines) and the insulationbetween the redundant wiring and the gate line can be kept with thesemiconductor layer retained, the semiconductor layer may be left as itis. Of course, it may be removed if the insulation state can be keptwhen removed. For example, when the semiconductor device is configuredas shown in FIG. 13, the crossings may be formed by adopting the deviceconfiguration as such, that is, a stack of an insulating layer, a firstsemiconductor layer and an n⁺-type semiconductor layer, a stack of agate insulating layer, a second semiconductor layer and an ohmic contactlayer, or the like, so that the crossings can be formed by a simpleprocess without providing additional steps.

[0043]FIG. 4 is an enlarged plan view showing an example of the layerconfiguration of a crossing S shown in FIGS. 1 and 2 and a sectionalview thereof. In FIG. 4, the Sig line and the Sig redundant wiring areelectrically insulated from each other and are arranged so as to form acrossing of the upper and lower lines. In the configuration shown in thefigure, if the semiconductor layer and the n⁺type semiconductor layereach have a considerably smaller electric conductivity than the wirings(lines) and the insulation between the redundant wiring and the gateline can be kept while leaving the layers, the layers may be left asthey are. Of course, they may be removed if the insulation state can bekept when removed.

[0044] In this embodiment, the Vg redundant wiring X and the Sigredundant wiring X are formed concurrently with the Vg lines and thesame insulating film as that for the photoelectric conversion elementsis used as an insulating layer therefor and the Vg redundant wiring Yand the Sig redundant wiring Y are formed concurrently with the Siglines. Therefore, there is no need for additional manufacturing steps toform the redundant wirings.

[0045] If a breaking occurs in the gate line Vg4 as shown by the point Ain FIGS. 1 and 2, the gate line Vg4 and the Vg redundant wiring areelectrically connected to each other by irradiating the crossing G ofthe gate line Vg4 and the Vg redundant wiring Y with a laser. Thus, gatedrive pulses are also applied to the elements T14, T24, T34 on thebroken line (gate line Vg4) through the Vg redundant wiring.

[0046] Further, if a breaking occurs in the signal line Sig1 as shown bythe point B in FIGS. 1 and 2, the signal line Sig1 and the Sig redundantwiring are electrically connected to each other by irradiating thecrossing S of the signal line Sig1 and the Sig redundant wiring X with alaser. Thus, an electric charge transferred with the gate drive pulsesapplied by the gate drive unit to the elements T12, T13, T14 on thebroken line (signal line Sig1) is read out by the readout unit throughthe Sig redundant wiring.

[0047] In summary, with the prior art, when a breaking of a line occurs,all the elements connected to the broken line can not be used to lowerthe yield of the panels, but according to this embodiment, even when abreaking of a line occurs, all the elements connected to the broken linecan be used, thereby preventing the lowering in the yield due tobreakings of the Vg or Sig lines without any decrease in aperture ratiofor the photoelectric conversion elements.

[0048] It should be appreciated that the two extra wirings of the Vgredundant wiring and the Sig redundant wiring are provided in thisembodiment, but each extra wiring accomplish the same technical effectas mentioned above, so that the number and use of the extra wirings tobe provided can be suitably selected depending on the number of possiblebreakings for each line.

[0049] [Embodiment 2]

[0050]FIG. 5 is an equivalent circuit diagram for showing aphotoelectric conversion device according to a second embodiment of thepresent invention.

[0051] In FIG. 5, reference numerals P01 to P54 denote semiconductorelements such as photoelectric conversion elements, radiation detectionelements or the like and reference numerals T01 to T54 denote switchingelements such as TFTs or the like. The gate electrode of each TFT isconnected to gate lines Vg1 to Vg4 or Vg5 to Vg8, which are common drivelines. The gate lines Vg1 to Vg4 are connected to a gate drive unit 1which controls the ON/OFF operations of the TFTs and similarly, the gatelines Vg5 to Vg8 are connected to a gate drive unit 2. The source ordrain electrode of each TFT is connected to common signal lines Sig0 toSig5, which are connected to a readout unit.

[0052] Further, three extra wirings are connected to the readout unit.Namely, the extra wirings are Sig redundant wirings 1, 2, 3 to be usedas redundant wirings for the Sig lines. The Sig redundant wiring 1 formscrossings with the lines Sig0 and Sig1, the Sig redundant wiring 2 formscrossings with the lines Sig2 and Sig3, and the Sig redundant wiring 3forms crossings with the lines Sig4 and Sig5 at an end of an insulatingsubstrate, respectively.

[0053] Each Sig redundant wiring used herein consists of a Sig redundantwiring X and a Sig redundant wiring Y and they are joined to each otherat the point C in the figure. An electric charge generated in thesemiconductor elements such as photoelectric conversion elements due toincidence of visible light or radiation is transferred to the signallines with gate drive pulses applied by the gate drive unit and is thenread out by the readout unit.

[0054] Each Sig line and a corresponding Sig redundant wiring areelectrically insulated from each other and are arranged so as to form acrossing of the upper and lower lines.

[0055] If a breaking occurs in the signal line Sig1 as shown by thepoint B in the figure, the signal line Sig1 and the Sig redundant wiring1 are electrically connected to each other by irradiating the crossing Sof the signal line Sig1 and the Sig redundant wiring 1 with a laser.Thus, an electric charge transferred with the gate drive pulses appliedby the gate drive unit to the elements T12, T13, T14 on the broken line(signal line Sig1) are read out by the readout unit through the Sigredundant wiring 1.

[0056] Therefore, the lowering in the yield due to breakings in the Siglines can be prevented. In addition, the lowering in the yield due to aplurality of breakings can be also prevented by forming a plurality ofredundant wirings as in this embodiment.

[0057] It should be appreciated that the extra wirings are connected tothe readout unit in this embodiment, but the number and use of the extrawirings can be suitably selected depending on the number of possiblebreakings in each line, for example, the extra wirings may be connectedto the gate drive unit so as to provide Vg redundant wirings when aplurality of breakings occur in the Vg lines.

[0058] [Embodiment 3]

[0059]FIG. 6 is an equivalent circuit diagram for showing aphotoelectric conversion device according to a third embodiment of thepresent invention.

[0060] In FIG. 6, reference numerals P11 to P44 denote semiconductorelements such as photoelectric conversion elements, radiation detectionelements or the like and reference numerals T11 to T44 denote switchingelements such as TFTs or the like. The gate electrode of each TFT isconnected to gate lines Vg1 to Vg4 which are common drive lines. Thegate lines Vg1 to Vg4 are connected to a gate drive unit which controlsthe ON/OFF operations of the TFTs. The source or drain electrode of eachTFT is connected to common signal lines Sig1 to Sig4, which areconnected to a readout unit.

[0061] In addition, an extra wiring (Vg redundant wiring) connected tothe gate drive unit acts as a redundant wiring for the Vg lines andforms a crossing with each Vg line outside a pixel area. Another extrawiring (Sig redundant wiring) connected to the readout unit acts as aredundant wiring for the Sig lines and forms a crossing with each Sigline outside the pixel area.

[0062] The Vg redundant wiring used herein consists of a Vg redundantwiring X and a Vg redundant wiring Y and they are joined to each otherat the point C in the figure. The Sig redundant wiring used hereinconsists of a Sig redundant wiring X and a Sig redundant wiring Y andthey are joined to each other at the point C in the figure.

[0063] An electric charge generated in the semiconductor elements suchas photoelectric conversion elements due to incidence of visible lightor radiation is transferred to the signal lines with gate drive pulsesapplied by the gate drive unit and is then read out by the readout unit.

[0064] Each Vg line and the Vg redundant wiring are electricallyinsulated from each other and are arranged so as to form a crossing ofthe upper and lower lines. Also, each Sig line and the Sig redundantwiring are electrically insulated from each other and are arranged so asto form a crossing of the upper and lower lines.

[0065] If a breaking occurs in the gate line Vg4 as shown by the point Ain the figure, applying a voltage between a pad Pvg4 for the gate lineVg4 and the Vg redundant wiring destroys an insulating film existingbetween the gate line Vg4 and the Vg redundant wiring to effectelectrical connection at the crossing G. Thus, gate drive pulses arealso applied to the elements T14, T24, T34 on the broken line (gate lineVg4) through the Vg redundant wiring.

[0066] If a breaking occurs in the signal line Sig1 as shown by thepoint B in the figure, applying a voltage between a pad Psig1 for thesignal line Sig1 and the Sig redundant wiring destroys an insulatinglayer to electrically connect the signal line Sig1 and the Sig redundantwiring at the crossing S. Thus, an electric charge transferred with thegate drive pulses applied by the gate drive unit to the elements T11,T12, T13, T14 on the broken line (signal line Sig1) are read out by thereadout unit through the Sig redundant wiring.

[0067] In summary, providing a pad and applying a voltage thereto breaksinsulation between a redundant wiring and a drive line and/or a signalline to effect electrical connection with the redundant wiring. Whensuch a pad is provided, the pad can be used to inspect for broken lines,and after the inspection, electrical breakdown may be produced byapplying a voltage higher than that for the inspection. Therefore, theconfiguration of this embodiment can prevent the lowering in the yielddue to breakings in the Vg or Sig lines. In addition, with thisembodiment, since the extra wirings are arranged outside the pixel area,the aperture ratio for the photoelectric conversion elements will not bereduced.

[0068] It should be appreciated that the two extra wirings of the Vgredundant wiring and the Sig redundant wiring are provided in thisembodiment, but each extra wiring accomplish the same technical effectas mentioned above, so that the number and use of the extra wirings tobe provided can be suitably selected depending on the number of possiblebreakings for each line.

[0069] [Embodiment 4]

[0070]FIG. 7 is an equivalent circuit diagram for showing aphotoelectric conversion device according to a fourth embodiment of thepresent invention.

[0071] In FIG. 7, reference numerals P11 to P44 denote semiconductorelements such as photoelectric conversion elements, radiation detectionelements or the like and reference numerals T11 to T44 denote switchingelements such as TFTs or the like. The gate electrode of each TFT isconnected to gate lines Vg1 to Vg4 which are common drive lines. Thegate lines Vg1 to Vg4 are connected to a gate drive unit which controlsthe ON/OFF operations of the TFTS. The source or drain electrode of eachTFT is connected to common signal lines Sig1 to Sig4, which areconnected to a readout unit.

[0072] Further, an extra wiring (Vg redundant wiring) is connected to areference potential (for example, GND) to act as a redundant wiring forthe Vg lines and forms a crossing with each Vg line outside a pixelarea.

[0073] The Vg redundant wiring used herein consists of a Vg redundantwiring X and a Vg redundant wiring Y and they are joined to each otherat the point C in the figure.

[0074] A electric charge generated in the semiconductor elements such asphotoelectric conversion elements, radiation detection elements or thelike due to incidence of visible light or radiation is transferred tothe signal lines with gate drive pulses applied by the gate drive unitand is then read out by the readout unit.

[0075] Each Vg line and the Vg redundant wiring are electricallyinsulated from each other and are arranged so as to form a crossing ofthe upper and lower lines.

[0076] If a breaking occurs in the gate line Vg4 as shown by the pointA, a crossing G of the gate line Vg4 and the Vg redundant wiring isirradiated with a laser to electrically connect the gate line Vg4 andthe Vg redundant wiring to each other. Thus, the potential of theelements T14, T24, T34 on the broken line (gate line Vg4) can be fixedto prevent the potential of the broken line (gate line Vg4) frombecoming unstable to adversely affect the pixels associated therewith.

[0077] In addition, in this embodiment, since the extra wiring isarranged outside the pixel area, the aperture ratio for thephotoelectric conversion elements will not be reduced. As the method ofeffecting electrical connection at the crossing G, there may also beused the method of applying a voltage to destroy an insulating film asdescribed in the third embodiment.

[0078] It should be appreciated that the single extra wiring, that is,the Vg redundant wiring is provided in this embodiment, but the numberand use of extra wirings can be suitably selected depending on thenumber of possible breakings in each wire, for example, a single Sigredundant wiring may be provided or two extra wirings may be providedwith one as a Vg redundant wiring and the other as a Sig redundantwiring.

[0079] [Embodiment 5]

[0080]FIG. 8 is an equivalent circuit diagram for showing aphotoelectric conversion device according to a fifth embodiment of thepresent invention.

[0081] In FIG. 8, reference numerals P11 to P44 denote semiconductorelements such as photoelectric conversion elements, radiation detectionelements or the like and reference numerals T11 to T44 denote switchingelements such as TFTs or the like. The gate electrode of each TFT isconnected to gate lines Vg1 to Vg4 which are common drive lines. Thegate lines Vg1 to Vg4 are connected to a gate drive unit which controlsthe ON/OFF operations of the TFTs. The source or drain electrode of eachTFT is connected to common signal lines Sig1 to Sig4, which areconnected to a readout unit.

[0082] Further, there exist a plurality of (in this case, four) extrawirings (Vg redundant wirings) connected to a gate drive unit, each ofwhich acts as a redundant wiring for the Vg lines and forms a crossingwith each Vg line at an end of an insulating substrate.

[0083] Each Vg redundant wiring used herein consists of a Vg redundantwiring X and a Vg redundant wiring Y and they are joined to each otherat the point C in the figure.

[0084] An electric charge generated in the semiconductor elements suchas photoelectric conversion elements, radiation detection elements orthe like due to incidence of visible light or radiation is transferredto the signal lines with gate drive pulses applied by the gate driveunit and is then read out by the readout unit.

[0085] Each Vg line and one Vg redundant wiring corresponding theretoare electrically insulated from each other and are arranged so as toform a crossing of the upper and lower lines.

[0086] If a breaking occurs in the gate line Vg4 as shown by the pointA, the crossing G of the gate line Vg4 and the Vg redundant wiring 4 isirradiated with a laser to electrically connect the gate line Vg4 andthe Vg redundant wiring 4 to each other. Thus, gate drive pulses arealso applied to the elements T14, T24, T34 on the broken line (gate lineVg4) through the Vg redundant wiring 4. Therefore, the lowering in theyield due to breakings of lines can be prevented.

[0087] Further, as the method of effecting electrical connection at thecrossing G, there may also be used the method of applying a voltage todestroy an insulating film as described in the third embodiment.

[0088] It should be appreciated that the four extra wirings, that is,the four Vg redundant wirings are provided in this embodiment, but thenumber and use of extra wirings can be suitably selected depending onthe number of possible breakings in each wire, for example, Sigredundant wirings may be provided.

[0089] [Embodiment 6]

[0090]FIG. 9 is a schematic sectional view for showing a radiationdetection device according to a sixth embodiment of the presentinvention. FIG. 10 is a plan view of the device shown in FIG. 9. Theradiation detection device of this embodiment has an energy converterthat converts a radiation directly into an electric charge, such asamorphous selenium (a—Se), GaAs or the like.

[0091]FIG. 9 shows a common electrode 201, an electric charge collectingelectrode 203 for collecting an electric charge converted by an energyconverter 202, storage capacitors 204 for storing the electric chargecollected by the electric charge collecting electrode 203, and switchingelement TFTs 121 for controlling the readout of the electric chargestored by the storage capacitors 204. In this device, a plurality ofpixels are formed by dividing the electric charge collecting electrode203 into a plurality of sections.

[0092]FIG. 10 shows a pixel area 119 having a plurality sets of anelectric charge collecting electrode 203 and other components,integrating circuits 126 having amplifiers 122 for amplifying theelectric charge read out from the pixel area 119 and capacitors CR0 toCR3, data signal lines D0 to D3 for connecting the pixel area 119 andthe integrating circuits 126 to each other, and gate drive lines G1 toG3 connected to the gate terminals of the TFTs 121. Here, the line D0 isan extra wiring, that is, a redundant wiring which consists of lines D0Xand D0Y, and the lines D0X and D0Y are arranged in superposition with aninsulating film therebetween and are connected to each other at thepoint C in the figure. The line D0 is also in superposition to and hascrossings with the data signal lines D1 to D3 outside the pixel area andeach crossing is electrically insulated.

[0093] If a breaking occurs in the line D2 as shown by the point V inFIG. 10, the crossing Z is irradiated with a laser to electricallyconnect the lines D2 and D0 to each other, thereby enabling readout ofan electric charge through the broken line. Therefore, the lowering inthe yield due to breakings of data signal lines can be prevented. If theenergy converter 202 has a small electric conductivity, the crossingsmay be formed with the energy converter 202 unremoved, so thatadditional process steps to remove the semiconductor layer of the energyconverter 202 can be omitted.

[0094] It should be appreciated that this embodiment is configured so asto connect the extra wiring, that is, the redundant wiring to the datasignal lines but it may be configured so as to connect the extra wiringto the gate drive lines or, of course, to combine the both connectingmanners.

[0095] [Embodiment 7]

[0096] Next, an implementation of the radiation detection device whichuses the semiconductor device according to the present invention todetect a radiation such as X-ray, etc. and a radiation imaging systemhaving the radiation detection device will be described below. As anexample of the radiation imaging system, the case of an X-ray diagnosticsystem will be taken.

[0097]FIGS. 14A and 14B are a schematic block diagram and a schematicsectional view for showing an implementation of the radiation detectiondevice to detect a radiation such as X-ray comprised of a phosphorbonded to the semiconductor device according to the present invention.

[0098] A plurality of photoelectric conversion elements or radiationdetection elements and switching elements such as TFTs are formed ineach a-Si (amorphous silicon) sensor substrate 6011, to which flexiblecircuit boards 6010 having shift registers SR1 and integrated circuitsIC for detection mounted thereon are connected. The sides of theflexible circuit boards 6010 opposite to the a-Si substrate areconnected to the circuit boards PCB1, PCB2. A plurality of the a-Sisensor substrates 6011 are bonded on the upper surface of the base 6012and a lead sheet 6013 for protecting memories 6014 in processing unit6018 from X-rays is mounted on the bottom of the base 6012 forming thelarge photodetecting device. On the a-Si sensor substrate 6011 is vapordeposited a phosphor 6030 as a wavelength converter such as CsI forconverting an incident radiation to visible light. Here, if asemiconductor material which is directly sensitive to a radiation isused, it is not necessary to provide the wavelength converter such as aphosphor or the like. In this embodiment, the whole device is housed ina case 6020 made of carbon fiber, as illustrated in FIG. 14B.

[0099]FIG. 15 shows application of the above described radiationdetection device to an X-ray diagnostic system.

[0100]FIG. 15 is a view showing an example of an X-ray diagnostic systemprovided with the above information reading apparatus.

[0101] X-rays 6060 generated in an X-ray tube 6050 pass through thechest part 6062 of a patient or subject 6061 and is then incident on thephotodetecting device 6040. The incident X-rays contain an internalinformation of the body of the patient or subject 6061. Incorrespondence to the incidence of X-rays the phosphor emits light,which is photoelectrically converted to provide an electricalinformation such as an electric charge. The information is converted toa digital signal, which is picture-processed in a picture processor 6070to be observed on a display 6080 in a control room.

[0102] In addition, the information can be transferred to a remotelocation through transmission means such as a telephone line 6090 andcan be displayed on a display 6081 in a doctor room or the like at adifferent location or can be stored in storage means such as opticaldisks to allow for diagnosis by a doctor at a remote location. Further,the information can be recorded on a film 6110 by a film processor 6100.

[0103] It should be appreciated that the term “radiation” used hereinrefers to X rays, α rays, β rays, or γ rays and the term “light” refersto electromagnetic waves within a range of wavelengths which can bedetected by a photoelectric conversion element and includes visiblelight.

What is claimed is:
 1. A semiconductor device comprising a plurality ofsemiconductor elements, a plurality of switching elements, a pluralityof drive lines for driving the switching elements, and a plurality ofsignal lines for reading out an electric charge detected by thesemiconductor elements provided on an insulating substrate, thesemiconductor device further comprising a redundant wiring which forms aplurality of crossings with at least one of the drive lines and thesignal lines and is electrically insulated from the at least one of thedrive lines and the signal lines at each crossing.
 2. The deviceaccording to claim 1, wherein when a breaking exists in at least one ofthe drive lines and the signal lines, the broken line and the redundantwiring are electrically connected at the crossing thereof.
 3. The deviceaccording to claim 2, wherein the broken line and the redundant wiringare electrically connected by irradiating the crossing with a laser. 4.The device according to claim 1, comprising a pad on at least one of thedrive lines and the signal lines.
 5. The device according to claim 2,wherein the broken line and the redundant wiring are electricallyconnected by applying a voltage therebetween.
 6. The device according toclaim 1, wherein the redundant wiring is connected to a referencepotential.
 7. The device according to claim 6, wherein the referencepotential is a ground potential.
 8. The device according to claim 2,wherein the electrical connection is effected in the crossing to fix thepotential of the broken line.
 9. The device according to claim 1,wherein a semiconductor layer is formed between the drive lines and theredundant wiring or between the signal lines and the redundant wiring,at the crossings.
 10. A semiconductor device comprising, on aninsulating substrate, a semiconductor element comprised of a firstelectrode layer, an insulating layer, a first semiconductor layer, ann⁺-type semiconductor layer, and a second electrode layer, and aswitching TFT comprised of a gate electrode layer, a gate insulatinglayer, a second semiconductor layer, and an ohmic contact layer, andhaving a drive line for driving the switching TFT and a signal line forreading out an electric charge detected by the semiconductor element,the device further comprising a redundant wiring, wherein the redundantwiring forms a plurality of crossings with at least one of the driveline and the signal line and the crossings are each comprised of theinsulating layer, the first semiconductor layer and the n⁺typesemiconductor layer or the gate insulating layer, the secondsemiconductor layer and the ohmic contact layer.
 11. A radiationdetection device comprising a common electrode, an energy converter forconverting a radiation directly into an electric charge, a plurality ofelectrodes for collecting the electric charge converted by the energyconverter, capacitors for storing the collected electric charge, andTFTs for reading out the stored electric charge, the device furthercomprising: data signal lines for reading out the stored electriccharge; gate drive lines connected to the TFTs; and a redundant wiringhaving a plurality of crossings with at least one of the data signallines and the gate drive lines.
 12. The device according to claim 11,wherein the energy converter comprises amorphous selenium or GaAs.
 13. Aradiation detection device having the semiconductor device as set forthin claim
 1. 14. The device according to claim 13, comprising awavelength converter.
 15. A radiation imaging system comprising: theradiation detection device as set forth in claim 13; signal processingmeans for processing a signal from the radiation detection device;recording means for recording a signal from the signal processing means;display means for displaying a signal from the signal processing means;transmission processing means for transmitting a signal from the signalprocessing means; and a radiation source for generating the radiation.